A social networking system, such as a social networking website, enables its users to interact with it and with each other through the system. The social networking system may create and store a record, often referred to as a user profile, in connection with the user. The user profile may include a user's demographic information, communication channel information, and personal interest. The social networking system may also create and store a record of a user's relationship with other users in the social networking system (e.g., social graph), as well as provide services (e.g., wall-posts, photo-sharing, or instant messaging) to facilitate social interaction between users in the social networking system. For example, a user of a social networking website can access an address book stored in the social networking website, look up a contact in the address book and connect with the contact through email.
Caller identification (or caller ID) is a telephone service, available in analog and digital phone systems and in most VoIP applications, that transmits a caller's phone number to a receiving party's telephony equipment (e.g., a mobile phone). When a person receives an incoming call on his phone from a caller, the phone can display the caller's phone number if caller ID service is available.